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Atrazine

Atrazine is a powerful member of the triazine class of herbicides, which characteristically possess three carbon and three nitrogen atoms in a six-membered ring. The chemical is often used to control plants such as chickweed, cocklebur, ragweed, and smartweed, and gains its effectiveness by inhibiting the process of photosynthesis.

Introduced in the 1970s, the herbicide atrazine is available in a variety of forms and is sold under an extensive array of trade names, such as Atranex, Atratol, Primatol, and Simazat. Due to its unusually long persistence in soil and the possibility of groundwater contamination, however, the chemical has been classified as a restricted use pesticide, and only those with the proper certification are able to legally purchase and apply the substance. Though quite effective against many broadleaf and grassy weeds, certain higher plant species are able to tolerate exposure to atrazine. Most scientists believe that this tolerance is a result of their ability to quickly breakdown the herbicide into non-toxic metabolites.

Categorized as a class III toxin, atrazine is slightly to moderately noxious to humans and other animals. The chemical, which may induce exposure symptoms that include nausea, abdominal pain, irritation of mucous membranes, and rash or redness of the skin, is readily absorbed dermally and through the gastrointestinal system. Atrazine may also enter the body through inhalation and has been shown to cause depression, coordination problems, tremors, slowed breathing, and hypothermia in test animals exposed to very high levels of the chemical.